With the diffusion of highways, the demand for tires provided with a self-sealing function has been increasing day by day, and many self-seal tires have been proposed until now.
According to the typical structure of conventional self-seal tires proposed, there are mainly two types, one type having an adhesive with high viscosity as a sealing material applied to the inner surface of the tire crown portion, and the other type having a sponge layer impregnated with a similar adhesive, which is provided on the inner surface of the tire crown portion.
The former type, however, involves a problem that, when the tire turns at a high seed, the adhesive can not seal a puncture in the vicinity of the shoulder portions, because it flows to the center side of the crown portion by centrifugal force.
The latter type needs to use an adhesive containing solvent in order to make the whole sponge layer sufficiently impregnated with the high viscosity adhesive. Therefore, an environmental problem due to volatiling of the solvent cannot be avoided. In addition, there is a drawback in handling of the tire, because the fully adhesive containing sponge layer is exposed on the tire inner surface side.
Though there is no direct relation with the air sealing, tires having an uneven dynamic balance are often obtained when manufactured. When the tire of this type is assembled to a rim, a weight for rectifying the dynamic balance is usually attached to the rim.
Such problem of tire dynamic balance rectification has been hitherto one of problems which bother those skilled in the art.